Drivers use visual clues to estimate when a traffic light will change color. Some drivers will speed up the vehicle when the traffic light is green to clear the intersection before the light changes to yellow or red. Seeing a traffic light turn yellow prior to reach the intersection will likely cause the driver to slow the vehicle in anticipation of the traffic light turning red. Drivers can use other visual clues from the traffic light, such as a left-turn arrow, to guess when the traffic light will change.